Calling 'isTouching' using 'ClassName' as the class of object to look for: if (isTouching(ClassName.class) is equivalent to: if (getOneIntersectingObject(ClassName.class) != null) If there is no need to know which specific object of the class ClassName your actor was intersecting with, then 'isTouching' would be sufficient. Oftentimes, however, like if the intersecting object needs to be removed from the world, you need to know which object was found to be intersecting. In that case, you would use: Actor intersector = getOneIntersectingObject(ClassName.class) if (intersector != null) { getWorld().removeObject(intersector); }

Had to re-size the app window (I have to solve the puzzle each time and get to the Stats screen before uploading or the Stats screen will end up with scrollbars).

When logged in, you can edit the scenario information. Near the 'Open in Greenfoot' download button, you should see 'edit scenario | delete scenario | get data'. Click on the 'edit' text.